Compass-handle-adjusting device.



PATENTED, JUNE 18,1907. o. G. MAYBE. coMPAss HANDLE ADJUSTING DEVICE.

APPLIUATION FILED JUNE 23,1906

oTTo G. MAYER, or STUTTGART, GERMANY.

COMPASS-HANDLE-ADJUSTING DEVICE.

Specification of Letters Patent.

Patented June 18, 1907.

Application filed June 23,1906. Serial No. 323,006.

To @ZZ whom, t moby concern:

Be it known that I, OTTO G. MAYER, a citi- Zen ofthe German Empire,residing at Stuttgart, in the Kingdom of Wrtemberg, Germany, haveinvented certain new and useful Improvements in and Relating to Compass-Handle-Adjusting Devices, of which the following is a description,reference being had to the accompanying drawings, and to the letters andfigures of reference marked thereon.

This invention relates to means employed in connection with a compass,whereby the handle will be automatically maintained in the middleposition, or a position equidistant relative to both legs of thecompass, at all positions of the compass-legs.

The improvement comprises disks, lying side by side, pivoted togetherand located between the heads of the compass, so as to control themovements of an arm, which enters the hollow handle of the compass, andadjusts the said handle to the middle position desired.

Referring to the drawings, Figure 1 is a side view of a compass, shownbroken away `at about the line B-B, provided with my improvements, Fig.2 is a sectional view, at right angles to Fig. l and on about the lineA-A of such figure g Fig. 3 is a view, similar to Fig. l of the positionof the parts when the compass is partly opened 5 Fig.` 4 is a like view,showing the compass o en to a wide extent; Fig. 5 is a sectional etailat about the line C-C of Fig. 4.

In the form of the invention illustrated, the compass is provided with ahandle having the hollow or bore y therein, and said handle is connectedwith a hollow frame, c, with its bore in line with the bore y, andhaving .depending arms, c, c. are pivotally fitted two compass-heads, Rand S, each having provided, at the center of its outer face with aconical recess. .Through each of the arms c, I provide threaded openingsalined with the conical recesses before mentioned, and in each of saidopenings I fit threaded screws O whose inner ends are formed to closelyfit the said conical recesses. Oneof said heads (It) is provided uponthe center of its inner face with a pin d, `and said pin rotatively fitsinto a recess at the center of the inner face of the head S.

Between the heads R and S, I tit two thin metal disks or plates, f andm, each of which is provided with a lower slot 7c (considerably Betweensaid legs wider than and through which the described pin d passes) andwith a single small opening at one side of said slot and about midway ofthe length thereof. As will be seen upon referring to Figs. 1, 3 and 5,the small openving of one disk is at the right of the slots in thedisks, while the small opening of the other disk is at the left of theslots.

One compass head (S, connected to compass-leg a) is provided with a piniat one side of the pivot-and said pin fits loosely into the smallopening in the adjacent disk (m), and the compass head R (connected withleg b) is provided with a pin e, at the opposite side of the pivot,which fits loosely into the small opening in the disk f, lying adjacentthereto and side by side with disk m. Each disk f and 'm is alsoprovided, at its upper edge, with slots Q, parallel with each other andwith the slot 7c, and both disks are pivotally secured together, bymeans of a rivet Z, at their upper edges and between the two slots Q. Anarm g is also connected, preferably by the rivet Z above named, to theadjusting means, and such arm slidably fits within the hollow or bore yof the handle. The connection of the arm is such that it will have arestricted movement about the rivet Z.

In practical operation, whenever a compass-leg is moved, the other legwill also be correspondingly moved, while the handle x will always beadjusted to the middle position. Thus, if the compass legs are movedcloser to one another, the pin e (on head It) will pull the disk f(which freely slides, upon pin CZ, by reason of the rocking of the slotwhich is wider than said pin) downwardly, and said disk will also, byreason of the connecting rivet Z, pull the disk m downwardly and with itthe leg a, rocking said disk m (as shown in Fig. 3). oppositely to diskf. In the same manner, the movement of the compasslegs apart will beegualized. In any event, however, the hand justed to the middleposition, by reason of both disks f and m, when moving relatively tothe'compass-heads, sliding freely upon the .pin d, and with the slots Q(which are wider than the sides of the hollow body c) freely slidingupon the outside of said body 5 thearm g being also slidably housedwithin the handle x, maintain such handle in the middle osition at allpositions of the disks f and m.

n opening and closing the compass-legs, the two disks f and m move aboutthe pins e IOO e Qc will always be adand i (acting as pivots located inthe compass-heads at points lying equidistant from and at op osite sidesof the plane of symmetry of t e compass-legs), and as the two disks arepivotally connected together by the pin Z, the latter and also the arm galso` remain at the middle position, no matter what the degree ofopening of the compass.

cured to the pivot connecting said disks and slidably engaging thehandle aforesaid.

2. A device secured to a compass for automatically retaining the handlethereof in the middle osition, comprising a pair of disks locatecbetween the compass-heads, each disk being pivotally connected with onecompass-head only, the ivots for said disks being located respective yin said heads at points lying equidistant from and at opposite sides ofthe plane of symmetry of the compass-legs, the two disks being pivotedtogether, and an arm secured to the pivot connecting said disks andslidably engaging the handle aforesaid.

3. A device secured to a compass for automatically retaining the handlethereof in the middle position, comprising a pair of disks locatedbetween and pivotally connected with the compass-heads, each disk beingprovided with a slot through which the pivot ofthe compass-heads assesandthe pivots for said disks being lbcated respectively at oppositesides of the slots aforesaid, the two disks being pivoted together, andan arm secured to the pivot connecting said disks and slidably engagingthe handles aforesaid.

4. A compass having a hollow handle and a hollow head provided witharms, compassheads pivoted between said arms, a pair of disks pivotallyconnected together and located between said compass-heads and pivotsengaging each compass-leg with one only of the disks, said disks havingslots for engaging the side-walls of the hollow head and slots for thepivot of the compass heads, and an arm secured to the pivot connectingsaid disks and slidablv engaging the handle aforesaid. l

In testimony whereof I aflix my signature. in presence of two witnesses.

OTTO G. MAYER.

Witnesses:

WALTER SoHwAEBEoH, RUDOLF BRECHT.

